Disclaimer: I do not own Supernatural
Things had been so different. It had been fun, at least that's what Dean told himself. Straightforward, hunting ghosts and the occasional creature, not easy. Never easy, but at least he knew where to point the gun. Now things were muddy, everything was always a shade of grey, some complex puzzle to sort out before you even got to the bad guy.
But then Dean thinks back, back to when it was him and John, hunting together. It had never been easy, it had never been fun. John had never been a dad, he was a commanding officer. Dean had pretended that it was okay, that it was just how things had to be for them, but he remembered before. Sam didn't, but Dean remembered. Before the fire, before Mary, Before John, before Sam, before Azazel, when it was mom, dad, Sammy, when things were right.
For all his bravado, Dean still lingered on those memories. When he slept he would see them, the life they could've had, what should've been, but then he would wake up in the world that had taken all that from him.
He was a pretender, always. To Sam most of all, not because it's what he needed to do, but because it was the only way he could get Sam to stay with him. No one ever stayed with Dean of their own accord, everyone always seemed in a mad dash to leave, to die, to go back to a life free of hunting. But Dean was in it, he couldn't not be, and he couldn't do it alone.
That was until Cas.
Castiel changed everything Dean knew. He changed everything Dean was to the very core of his torn and tattered soul, and he did it so effortlessly. Cas was on the opposite path, everything Dean knew, Cas seemed to do backwards. He showed up, he stuck around, he seemed inescapable at times, he seemed to want to be around Dean, to gravitate towards him. He went from Castiel, soldier, to Cas, Dean's most reliable, most loved, most trusted, friend. He didn't run away, it seemed like the thought had never even occurred to him, it seemed as if it had always been, the two of them together against whatever came at them.
It felt strange allowing himself to depend and rely on someone so completely, but in those dark cold nights, when Dean would feel the heat of the flames licking his cheeks, hear his father bark orders at him, get Sammy out, hear Sam's cold tones saying all he ever wanted to do was go back to Stanford, feel the claws of loneliness clench tighter around him, there would be a warm hand, breaking him free. A feather light blanket draped over him, cool lips gently kissing his neck, lulling him back into an easy sleep.
Cas would always chase the nightmares away.